Abstract 474: Higher Mortality From Cardiac Arrest in North Carolina versus Washington State and Denmark: Implications for Improving Systems of Care

Introduction: Survival from out-of-hospital cardiac arrest (OHCA) remains low and with major regional variation. This study explored differences in patients, care, and survival in patients with OHCA in North Carolina (NC), Washington State (WA), and Denmark. Methods: We identified a total of 17,277 adult patients with OHCA from the Cardiac Arrest Registry to Enhance Survival (CARES) registry and the Danish Cardiac Arrest Register of presumed cardiac cause from 2013-2014. Patients were categorized into three regions: two states in the United States (NC, 9.1 million inhabitants, WA, 7.5 million inhabitants) and the country of Denmark (5.8 million inhabitants). Outcomes of cardiopulmonary resuscitation (CPR) and defibrillation performed by either professional first responder or lay bystanders prior to emergency medical service (EMS) arrival, as well as overall survival. Data were analyzed using multivariable logistic regression analyses adjusted for age, sex, calendar year, location of arrest and witnessed status. Results: Patients in NC and WA were younger and had more racial variation compared to Denmark. Survival was 9.3% in NC, 14.5% in WA and 13.3% in Denmark. Using the Danish cohort as reference, the odds for bystander CPR and defibrillation in NC (CPR: OR 0.41, 95%CI 0.38-0.44; defibrillation: OR 0.30, 95%CI 0.23-0.38) and WA (CPR: OR 0.71, 95%CI 0.65-0.77; defibrillation: OR 0.41, 95%CI 0.31-0.53) were lower, respectively. CPR and defibrillation performed by either a bystander or a professional first responder prior to EMS arrival were higher in NC (CPR: OR 2.67, 95%CI 2.43-2.93; defibrillation: OR 2.72 95%CI 2.30-3.21), but not in WA (CPR: OR 1.01, 95%CI 0.92-1.11; defibrillation OR 0.73, 95%CI 0.58-0.90), respectively. Compared with Denmark, survival was lower in NC (OR 0.39, 95%CI 0.34-0.45) and WA (OR 0.83, 95%CI 0.72-0.95). Conclusion: Survival following OHCA was higher in Denmark and WA than in NC, and was associated with higher rates of bystander CPR and defibrillation. However, CPR and defibrillation prior to EMS arrival, mainly from professional first responders, was significantly higher in NC. A combination of both bystander and first responder interventions may be the optimal approach to improve outcomes of cardiac arrest.